The present invention relates to a sortation conveying system used to fulfill orders of intermingled articles such as assortments of books, video cassette containers, packaged software, compact disc containers, DVD containers or the like. More specifically, the present invention relates to a transition device for receiving horizontally supported discharged articles having a random orientation and directing the articles onto a vertically supported discharge stacking station for stacking the intermingled articles.
In large distribution applications, sortation conveying systems are used to fulfill orders of intermingled articles, such as assortments of books, video cassette containers, packaged software, DVD""s, compact disc containers, etc. One method of effectuating a sortation conveying system is to utilize a cross-belt conveyer system that comprises a train of individual cars each including one or more conveyors that can be selectively operated to discharge the articles contained on each car into a selected collection bin. Assorted articles are loaded onto the individual cars of the conveyor system and bar code information for each respective article is read. Based upon this information, a programmable computer controls the operation of the individual belts on each conveyor car such that the belts discharge the articles into the correct collection bin. The collection bins receive the articles and accumulate the articles in an unstacked manner. Once an order has been filled, workers take the articles from the bin and pack the orders for distribution.
A second type of sortation conveying system is shown in U.S. Pat. Nos. 6,296,437 and 6,302,638, each of which are owned by the assignee of the present application and are incorporated herein by reference. In the systems shown in these patents, articles are conveyed in a single file order along an edge surface and the individual articles are directed to one of a plurality of discharge stacking stations. The discharge stacking stations create an ordered stack of articles each standing on its edge surface. When the appropriate number of articles are accumulated within the stacking station, a worker simply places the ordered stack into a container for shipping. As can be understood by the foregoing description and the subject matter of each patent, stacking the sorted articles minimizes damage to the articles being handled. Additionally, the ordered stack of intermingled articles increases the packing efficiency and reduces wasted space and packing times.
Although the sortation and stacking system shown in the xe2x80x2437 and xe2x80x2638 patents is effective in stacking articles received in a single file from a conveying system, the discharge stacking stations are currently unable to handle articles discharged in a random orientation and supported horizontally on one of the article""s face surfaces. The conveying system described in each of the two prior patents provides articles to the discharge stacking station on edge such that discharge stacking station can create an ordered stack of articles. In a cross-belt conveyor system, articles are discharged with a random orientation and supported on one of the flat face surfaces.
Therefore, a need exists for a transition device to receive articles having a random orientation from a cross-belt conveyor system or other similar conveyor system. The transition device must redirect the articles from the random, horizontal orientation to a vertical orientation in which the article rests upon one of its edge surfaces. Once the article is oriented in the proper manner, the transition device needs to supply the article to the discharge stacking station for accumulation. Further, a need exists for a transition device that allows the articles to be fed at a high rate of speed and at a random orientation such that the transition device retards the movement of the article and presents the article in a condition to be stacked by the discharge stacking station.
The present invention is a transition station for receiving articles discharged from a supply conveyor assembly, such as a cross-belt conveyor. The articles discharged from the cross-belt conveyor have a random orientation and are generally horizontally oriented. The transition station of the present invention reorients each of the intermingled articles onto an edge surface. The intermingled articles from the transition station are transferred to a discharge stacking station for stacking the articles in a side-by-side condition for loading into a shipping container.
The transition station of the present invention includes a transition plate positioned to receive the discharged articles from the cross-belt conveyor. The transition plate has a curved outer surface that extends from a first end to a second end. The first end of the transition plate is generally horizontal and receives the dispensed articles.
As the dispensed articles move along the transition plate, the outer surface of the transition plate is curved from a generally horizontal orientation at the first end to a generally vertical orientation at the second end. The second end of the transition plate is spaced slightly above a discharge chute. The discharge chute is positioned to receive an edge surface of the article after the article has left the transition plate.
In the preferred embodiment of the invention, the discharge plate includes a bottom plate that is inclined to direct articles from the discharge chute to the discharge stacking station. The bottom plate of the discharge chute is preferably coated with a friction-reducing coating, such as teflon, to aid in the movement of articles along the discharge chute toward the discharge stacking station.
The transition station includes a deflection hood that is spaced from the transition plate to define a product gap. The deflection hood extends from a top end to a bottom end and includes a curved inner surface. The curved inner surface is spaced from the transition plate to define the product gap.
The deflection hood is pivotally mounted between a pair of side brackets such that the deflection plate can pivot upon contact with an article discharged from the supply conveyor assembly. The deflection hood is mounted between the pair of side brackets such that the weight of the deflection hood biases the deflection hood into a first position. When the deflection hood is in the first position, the product gap has its minimum width. In the preferred embodiment of the invention, a movement limiting bracket is attached to the back surface of the deflection hood to define the first position.
As an article contacts the deflection hood, the deflection hood pivots from the first position to the second position. When the deflection hood is in the second position, the product gap has its maximum width. In the preferred embodiment of the invention, a pivot stop member is included on the transition station to contact the back surface of the deflection hood to define the second position for the deflection hood.
The product gap defined by the deflection hood and the transition plate directs articles from the transition plate to the discharge chute. The pivoting movement of the deflection hood absorbs the inertia of the article and allows the article to be supported by its edge surface. The deflection hood directs the article to the discharge stacking station for accumulation in a side-by-side stack.
The product gap defined by the deflection hood and the transition plate can vary between the minimum width when the deflection hood is in the first position and the maximum width when the deflection hood is in its second position. Preferably, the maximum width of the product gap is less than the width and height of each type of article being sorted such that the articles can pass through the product gap only with one of the edge surfaces leading. Thus, after the article passes through the product gap, one of the edge surfaces is directed into contact with the discharge chute such that the article can be properly stacked by the discharge stacking station.
Various other features, objects and advantages of the invention will be made apparent from the following description taken together with the drawings.